A free software for sand and gravel embayed beach modelling: PhoEbuS- parabolic equation shape     

Chiara F. Schiaffino  Massimo Brignone  Marco Ferrari 《Earth Science Informatics》2013,6(3):165-173

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Water quality and risk assessment of dug wells: a case study for a poor community in the city of São Paulo, Brazil     

Alexandra V. Suhogusoff  Ricardo Hirata  Luiz Carlos K. M. Ferrari 《Environmental Earth Sciences》2013,68(3):899-910

Sparsely populated areas, or peripheral communities commonly lack access to a public water supply and sewerage systems. The inhabitants of these areas must make use of excavated wells to provide their water needs, and cesspits for domestic wastewater disposal. These on-site sanitation systems can release pathogens and nutrients into shallow groundwater. These poor communities urgently require cheap and efficient techniques for the detection of sanitary conditions, in order to prevent contamination of the water resources supplied by dug wells. The sanitary risk assessment methodology, applied in an irregular settlement south of the city of São Paulo, was based on a questionnaire with yes/no questions (risk factors), which allowed the identification of problems related to the well construction and operation, and the presence of potential contamination sources in its vicinity. These risk factors were compared against nitrate and bacterial analysis using the clustering statistical method, to verify the relationship between contamination and certain aspects surveyed in the questionnaire. Questions that were more related to contaminated wells were those concerning the presence of cover and its integrity; gaps between mouth and cover; the surrounding pavement and presence of ground irregularities; infiltration in the well casing; water-suspended materials; and proximity to contamination sources. Contamination models based on variograms allowed to observe that bacterial contamination presented a strong localized component, which was associated frequently with the way residents handled the wells, whereas nitrate contamination was related more to a regional (spatial) component; that is, the distance between wells and cesspits.  相似文献   

A 3-dimensional calculation of the atmospheric neutrino fluxes     

G. Battistoni  A. Ferrari  P. Lipari  T. Montaruli  P. R. Sala  T. Rancati 《Astroparticle Physics》2000,12(4):315-333

An extensive 3-dimensional Monte Carlo calculation of the atmospheric neutrino flux is in progress with the FLUKA Monte Carlo code. The results are compared to those obtained under the 1-dimensional approximation, where secondary particles and decay products are assumed to be collinear to the primary cosmic ray, as usually done in most of the already existing flux calculations. It is shown that the collinear approximation gives rise to a wrong angular distribution of neutrinos, essentially in the Sub-GeV region. However, the angular smearing introduced by the experimental inability of detecting recoils in neutrino interactions with nuclei is large enough to wash out, in practice, most of the differences between 3-dimensional and 1-dimensional flux calculations. Therefore, the use of the collinear approximation should not have introduced a significant bias in the determination of the flavor oscillation parameters in current experiments.  相似文献   

Qualitative Rockfall Hazard Assessment: A Comprehensive Review of Current Practices     

F. Ferrari  A. Giacomini  K. Thoeni 《Rock Mechanics and Rock Engineering》2016,49(7):2865-2922

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Relationship between the optical properties of chromophoric dissolved organic matter and total concentration of dissolved organic carbon in the southern Baltic Sea region   总被引：10，自引：0，他引：10  

Giovanni M. Ferrari  Mark D. Dowell  Stefania Grossi  Cristina Targa 《Marine Chemistry》1996,55(3-4)

Absorption and fluorescence of chromophoric dissolved organic matter (CDOM) and dissolved organic carbon (DOC) measurements were performed during three oceanographic surveys in 1994 in the southern Baltic Sea (Polish area of the Baltic Proper). DOC was measured both by high-temperature catalytic oxidation (HTCO) and low-temperature oxidation (LTO) conventional persulphate methods. CDOM fluorescence was shown to be highly correlated with absorption, with the same regression parameters, despite the seasonal change in different hydrographic conditions and the fluorescence quantum yield variations (1.23 ± 0.07 in April and 0.97 ± 0.12 in September). The results show a good correlation between the optical parameters and DOC although ˜ 70% of the DOC does not display significant absorption in the UV-visible range (350–750 nm). The non-absorbing DOC measured with HTCO method appears unaffected by seasonal changes. Consequently, total DOC can be predicted by optical methods using remote sensing techniques. The non-absorbing DOC measured by LTO method varies from 62% (April) to 76% (September), which implies that there is requirement for estimates on a seasonal basis.  相似文献   

Correction to: Rip current hazard assessment on a sandy beach in Liguria,NW Mediterranean     

Mucerino  Luigi  Carpi  Luca  Schiafno  Chiara F.  Pranzini  Enzo  Sessa  Eleonora  Ferrari  Marco 《Natural Hazards》2021,105(1):157-157

Natural Hazards - The article was published showing the first two author names in the wrong order.  相似文献   

Volume change response and fabric evolution of granular MX80 bentonite along different hydro-mechanical stress paths     

Ferrari  Alessio  Bosch  Jose A.  Baryla  Patrycja  Rosone  Marco 《Acta Geotechnica》2022,17(9):3719-3730

Despite the increasing understanding of bentonite behaviour, there is still missing evidence on how different hydro-mechanical loadings, including sequences of hydration and compression, affect the fabric and the volume change behaviour of the material. It is generally assumed that the interplay between the behaviour of clay assemblages and the overall fabric of the material is the reason of having final states that are dependent on the stress path followed. Here the results of an experimental campaign aiming to study these factors are reported and discussed. Free swelling and swelling pressure tests were performed, both followed by compression to a relatively high stress. The experimental program involved various samples that were dismantled at intermediate states in order to perform microstructural observations by means of mercury intrusion porosimetry and electronic scanning microscopy. It was observed that while the void ratio at a given stress level depends on the stress path, subsequent compression led to a unique virgin compression line. The data obtained at the microscale gave further insight for an interpretation of the volume change behaviour observed at the macroscale, showing that at high stress the material tends to recover the same fabric regardless of the path to saturation.

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Rip current hazard assessment on a sandy beach in Liguria,NW Mediterranean     

Mucerino  Luigi  Carpi  Luca  Schiaffino  Chiara F.  Pranzini  Enzo  Sessa  Eleonora  Ferrari  Marco 《Natural Hazards》2021,105(1):137-156

Natural Hazards - Rip currents are one of the most significant environmental hazards for beachgoers and are of interest to coastal scientists. Several studies have been conducted to understand rip...  相似文献   

PCBs and PAHs in sea-surface microlayer and sub-surface water samples of the Venice Lagoon (Italy)   总被引：1，自引：0，他引：1  

Manodori L  Gambaro A  Piazza R  Ferrari S  Stortini AM  Moret I  Capodaglio G 《Marine pollution bulletin》2006,52(2):184-192

Polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) are two classes of micropollutants intensively monitored and regulated due to their toxicity, persistency and wide diffusion. Their concentrations have been investigated in sea-microlayer (SML) and sub-surface water (SSW) samples collected at two sites of the Venice Lagoon, a fragile ecosystem highly influenced by industrial and anthropogenic emissions. The total sigmaPCB concentration varies from 0.45 ng/l to 2.1 ng/l in SSW while a clear enrichment is observed in the SML, where it ranges from 1.2 ng/l to 10.5 ng/l. The total sigmaPAH concentration shows marked differences between the two stations and varies from 12.4 ng/l to 266.8 ng/l in SSW; in SML it is more uniform and ranges from 19.6 ng/l to 178.9 ng/l. The enrichment factors are not larger than 1 for both pollutants in the 'dissolved' phase, while they are most significant for the 'particulate' phase (sigmaPCB: 5-9; sigmaPAH: 4-14).  相似文献   

Structure of self-gravity wakes in Saturn's A ring as measured by Cassini CIRS     

C. Ferrari  S. Brooks  C. Leyrat  L. Spilker 《Icarus》2009,199(1):145-153

The CIRS infrared spectrometer onboard the Cassini spacecraft has scanned Saturn's A ring azimuthally from several viewing angles since its orbit insertion in 2004. A quadrupolar asymmetry has been detected in this ring at spacecraft elevations ranging between 16° to 37°. Its fractional amplitude decreases from 22% to 8% from 20° to 37° elevations. The patterns observed in two almost complete azimuthal scans at elevations 20° and 36° strongly favor the self-gravity wakes as the origin of the asymmetry. The elliptical, infinite cylinder model of Hedman et al. [Hedman, M.M., Nicholson, P.D., Salo, H., Wallis, B.D., Buratti, B.J., Baines, K.H., Brown, R.H., Clark, R.N., 2007. Astron. J. 133, 2624-2629] can reproduce the CIRS observations well. Such wakes are found to have an average height-to-spacing ratio H/λ=0.1607±0.0002, a width-over-spacing W/λ=0.3833±0.0008. Gaps between wakes, which are filled with particles, have an optical depth τG=0.1231±0.0005. The wakes mean pitch angle ΦW is 70.70°±0.07°, relative to the radial direction. The comparison of ground-based visible data with CIRS observations constrains the A ring to be a monolayer. For a surface mass density of 40 g cm⁻² [Tiscarino, M.S., Burns, J.A., Nicholson, P.D., Hedman, M.M., Porco, C.C., 2007. Icarus 189, 14-34], the expected spacing of wakes is λ≈60 m. Their height and width would then be H≈10 m and W≈24 m, values that match the maximum size of particles in this ring as determined from ground-based stellar occultations [French, R.G., Nicholson, P.D., 2000. Icarus 145, 502-523].  相似文献